Drop attacks stem from diverse mechanisms, including orthopedic causes (for example, leg weakness and knee instability), hemodynamic causes (for example, transient vertebrobasilar insufficiency, a type of interruption of blood flow to the brain), and neurologic causes (such as epileptic seizures or unstable vestibular function), among other reasons ...
ËpÃ¦l i-) adj. (sometimes l.c.) of, designating, or characteristic of the early phase of the Stone Age: usu. divided into three periods (Lower Paleolithic, c2,000,000âc200,000 b.c., Middle Paleolithic, c150,000âc40,000 b.c., Upper Paleolithic, c40,000âc10,000 b.c.).
It extends from the earliest known use of stone tools, probably by Homo habilis initially, 2.6 million years ago, to the end of the Pleistocene around 10,000 BP. The Paleolithic era is followed by the Mesolithic. The date of the PaleolithicâMesolithic boundary may vary by locality as much as several thousand years.